DATASHEET
ISL4241E, ISL4243E
QFN Packaged, ±15kV ESD Protected, +2.7V to +5.5V, 10Nanoamp, 250kbps,
RS-232 Transmitters/Receivers
Intersil’s ISL4241E, ISL4243E devices are 2.7V to 5.5V
powered RS-232 transmitters/receivers which meet
ElA/TIA-232 and V.28/V.24 specifications, even at
VCC = 3.0V. Additionally, they provide ±15kV ESD protection
(IEC61000-4-2 Air Gap and Human Body Model) on
transmitter outputs and receiver inputs (RS-232 pins).
Targeted applications are PDAs, Palmtops, and notebook
and laptop computers where the low operational, and even
lower standby, power consumption is critical. Efficient
on-chip charge pumps, coupled with manual and automatic
power-down functions, reduce the standby supply current to
a 10nA trickle. Tiny 5mmx5mm Quad Flat No-Lead (QFN)
packaging and the use of small, low value capacitors ensure
board space savings as well. Data rates greater than
250kbps are guaranteed at worst case load conditions.
The ISL4241E, ISL4243E’s are 3 driver, 5 receiver devices
that, coupled with the 5x5 QFN package, provide the
industry’s smallest, lowest power complete serial port
suitable for PDAs, and laptop or notebook computers. The
32 Ld 5X5 QFN requires 60% less board area than a 28 Ld
TSSOP, and is nearly 20% thinner. The devices also include
a noninverting always-active receiver for “wake-up”
capability.
The ISL4243E features an automatic power-down function
that powers down the on-chip power-supply and driver
circuits. This occurs when an attached peripheral device is
shut off or the RS-232 cable is removed, conserving system
power automatically without changes to the hardware or
operating system. It powers up again when a valid RS-232
voltage is applied to any receiver input.
Table 1 summarizes the features of both the ISL4241E and
ISL4243E, while Application Note AN9863 summarizes the
features of each device comprising the 3V RS-232 family.
FN8037
Rev 7.00
Jun 10, 2010
Features
• Pb-Free Available (RoHS compliant)
• Parameters Fully Specified for 10% Tolerance Supplies
and Full Industrial Temp Range
• Available in Small QFN (5mmx5mm) Package which is
60% Smaller than a 28 Lead TSSOP
• ESD Protection for RS-232 I/O Pins to ±15kV (IEC61000)
• Meets EIA/TIA-232 and V.28/V.24 Specifications at 3V
• RS-232 Compatible with V
CC
= 2.7V
• On-Chip Voltage Converters Require Only Four External
0.1µF Capacitors
• Manual and Automatic Power-down Features
• Receiver Hysteresis For Improved Noise Immunity
• Guaranteed Minimum Data Rate . . . . . . . . . . . . . 250kbps
• Wide Power Supply Range . . . . . . Single +2.7V to +5.5V
• Low Supply Current in Power-down State . . . . . . . . .10nA
Applications
• Any Space Constrained System Requiring RS-232 Ports
- Battery Powered, Hand-Held, and Portable Equipment
- Laptop Computers, Notebooks
- PDAs and Palmtops, Data Cables
- Cellular/Mobile Phones, Digital Cameras, GPS
Receivers
Related Literature
• Technical Brief TB363 “Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
• ”Technical Brief TB379 “Thermal Characterization of
Packages for ICs”
• Technical Brief TB389 “PCB Land Pattern Design and
Surface Mount Guidelines for QFN Packages”
TABLE 1. SUMMARY OF FEATURES
NO. OF
MONITOR Rx.
QFN PKG.
(R
OUTB
)
AVAILABLE?
YES
YES
2
1
DATA
RATE
(kbps)
250
250
MANUAL
POWER-
DOWN?
YES
YES
AUTOMATIC
POWER-
DOWN
FUNCTION?
NO
YES
PART NUMBER
ISL4241E
ISL4243E
NO. OF NO. OF
Tx.
Rx.
3
3
5
5
Rx. ENABLE
FUNCTION?
YES
NO
READY
OUTPUT?
NO
NO
FN8037 Rev 7.00
Jun 10, 2010
Page 1 of 14
ISL4241E, ISL4243E
Ordering Information
PART
NUMBER
ISL4241EIR
ISL4241EIR-T*
ISL4241EIRZ (Note)
ISL4241EIRZ-T* (Note)
ISL4243EIR
ISL4243EIR-T*
ISL4243EIRZ (Note)
ISL4243EIRZ-T* (Note)
PART MARKING
ISL 4241EIR
ISL 4241EIR
ISL4241 EIRZ
ISL4241 EIRZ
ISL 4243EIR
ISL 4243EIR
ISL4243 EIRZ
ISL4243 EIRZ
TEMP. RANGE
(°C)
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
PACKAGE
32 Ld QFN
32 Ld QFN
Tape & Reel
32 Ld QFN (Pb-Free)
32 Ld QFN
Tape & Reel (Pb-Free)
32 Ld QFN
32 Ld QFN
Tape & Reel
32 Ld QFN (Pb-Free)
32 Ld QFN
Tape & Reel (Pb-Free)
PKG. DWG. #
L32.5x5B
L32.5x5B
L32.5x5B
L32.5x5B
L32.5x5B
L32.5x5B
L32.5x5B
L32.5x5B
*Please refer to TB347 for details on reel specifications.
NOTE: These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100%
matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil
Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
Pinouts
ISL4241E
(32 LD QFN)
TOP VIEW
V
CC
C2+
C1+
C2-
NC
C2-
NC
NC
V+
V-
V-
ISL4243E
(32 LD QFN)
TOP VIEW
V
CC
26
C2+
C1+
V+
NC
25
24
23
22
21
PD
20
19
18
17
9
NC
10
T3
IN
11
T2
IN
12
T1
IN
13
R5
OUT
14
R4
OUT
15
R3
OUT
16
NC
GND
C1-
FORCEON
FORCEOFF
INVALID
R2
OUTB
R1
OUT
R2
OUT
32
R1
IN
R2
IN
R3
IN
R4
IN
R5
IN
T1
OUT
T2
OUT
T3
OUT
1
2
3
4
5
6
7
8
9
NC
31
30
29
28
27
26
25
24
23
22
21
GND
C1-
EN
SHDN
R1
OUTB
R2
OUTB
R1
OUT
R2
OUT
R1
IN
R2
IN
R3
IN
R4
IN
R5
IN
T1
OUT
T2
OUT
T3
OUT
1
2
3
4
5
6
7
8
32
31
30
29
28
27
PD
20
19
18
17
10
T3
IN
11
T2
IN
12
T1
IN
13
R5
OUT
14
R4
OUT
15
R3
OUT
16
NC
FN8037 Rev 7.00
Jun 10, 2010
Page 2 of 14
ISL4241E, ISL4243E
Pin Descriptions
PIN
V
CC
V+
V-
GND
C1+
C1-
C2+
C2-
T
IN
T
OUT
R
IN
R
OUT
R
OUTB
INVALID
System power supply input (2.7V to 5.5V).
Internally generated positive transmitter supply (+5.5V).
Internally generated negative transmitter supply (-5.5V).
Ground connection. This is also the potential of the thermal pad (PD).
External capacitor (voltage doubler) is connected to this lead.
External capacitor (voltage doubler) is connected to this lead.
External capacitor (voltage inverter) is connected to this lead.
External capacitor (voltage inverter) is connected to this lead.
TTL/CMOS compatible transmitter Inputs.
±15kV ESD Protected
,
RS-232 level (nominally ±5.5V) transmitter outputs.
±15kV ESD Protected
,
RS-232 compatible receiver inputs.
TTL/CMOS level receiver outputs.
TTL/CMOS level, noninverting, always enabled receiver outputs.
Active low output that indicates if no valid RS-232 levels are present on any receiver input.
FUNCTION
FORCEOFF Active low to shut down transmitters and on-chip power supply. This overrides any automatic circuitry and FORCEON (see Table 2).
FORCEON
EN
SHDN
NC
PD
Active high input to override automatic power-down circuitry thereby keeping transmitters active. (FORCEOFF must be high).
Active low receiver enable control.
Active low input to shut down transmitters and on-board power supply, to place device in low power mode.
No Connection
Exposed Thermal Pad. Connect to GND.
FN8037 Rev 7.00
Jun 10, 2010
Page 3 of 14
ISL4241E, ISL4243E
Typical Operating Circuits
ISL4241E
+3.3V
+
+3.3V
0.1µF
26
V
CC
V+
27
+ C
3
0.1µF
C
4
0.1µF
+
T1
OUT
7
8
T2
OUT
T3
OUT
RS-232
LEVELS
C
1
0.1µF
C
2
0.1µF
+
+
ISL4243E
0.1µF
28
23
29
30
C1+
C1-
C2+
C2-
26
V
CC
27
V+
31
+
C
3
0.1µF
C
1
0.1µF
C
2
0.1µF
T1
IN
T2
IN
T3
IN
R1
OUTB
R2
OUTB
TTL/CMOS
LOGIC
LEVELS
R1
OUT
28
C1+
+
23
C1-
29
C2+
+
30
C2-
12
11
10
20
19
V-
T
1
T
2
T
3
31
6
+
V-
T
1
C
4
0.1µF
+
T1
IN
12
6
T1
OUT
7
T2
OUT
8
T3
OUT
RS-232
LEVELS
T2
IN
T3
IN
11
10
T
2
T
3
19
R2
OUTB
1
R
1
5k
2
R
2
5k
3
R
3
5k
4
R
4
5k
5
EN
R
5
5k
R5
IN
R5
OUT
13
22
SHDN
GND
24
V
CC
TO POWER
CONTROL
LOGIC
21
20
R
5
FORCEON
5k
R4
IN
R3
IN
RS-232
LEVELS
15
R3
OUT
R
3
R4
OUT
14
R
4
5k
5
R5
IN
5k
4
R4
IN
R2
IN
R1
IN
TTL/CMOS
LOGIC
LEVELS
R2
OUT
18
R1
OUT
R
1
17
R
2
5k
3
R3
IN
RS-232
LEVELS
5k
2
R2
IN
1
R1
IN
18
R2
OUT
17
15
R3
OUT
14
R4
OUT
13
22
21
R5
OUT
V
CC
FORCEOFF
INVALID
GND
24
FN8037 Rev 7.00
Jun 10, 2010
Page 4 of 14
ISL4241E, ISL4243E
Absolute Maximum Ratings
V
CC
to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6V
V+ to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7V
V- to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +0.3V to -7V
V+ to V- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14V
Input Voltages
T
IN
, FORCEOFF, FORCEON, EN, SHDN . . . . . . . . . -0.3V to 6V
R
IN
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25V
Output Voltages
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.2V
R
OUT
, INVALID. . . . . . . . . . . . . . . . . . . . . . . . -0.3V to V
CC
+0.3V
Short Circuit Duration
T
OUT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
ESD Rating . . . . . . . . . . . . See “ESD PERFORMANCE” on page 7
Thermal Information
Thermal Resistance (Typical, Notes 1, 2)
JA
(°C/W)
JC
(°C/W)
32 Ld QFN Package. . . . . . . . . . . . . . .
32
2.0
Maximum Storage Temperature Range . . . . . . . . . .-65°C to +150°C
Pb-Free Reflow Profile. . . . . . . . . . . . . . . . . . . . . . . . .see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Operating Conditions
Temperature Range
ISL4241EIR, ISL4243EIR . . . . . . . . . . . . . . . . . . .-40°C to +85°C
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.
NOTE:
1.
JA
is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See
Tech Brief TB379, and Tech Brief TB389.
2. For
JC
, the “case temp” location is the center of the exposed metal pad on the package underside.
Electrical Specifications
Test Conditions: V
CC
= 3V to 5.5V, C
1
to C
4
= 0.1µF; Unless Otherwise Specified.
Typicals are at T
A
= +25°C
TEST CONDITIONS
TEMP
(°C)
MIN
(Note 4)
TYP
MAX
(Note 4) UNITS
PARAMETER
DC CHARACTERISTICS
Operating Voltage Range
Supply Current, Automatic
Power-down
Supply Current, Power-down
Full
All R
IN
Open, FORCEON = GND, FORCEOFF = V
CC
(ISL4243E Only)
All R
IN
Open, FORCEOFF = SHDN = GND
All Outputs Unloaded,
FORCEON = FORCEOFF = SHDN = V
CC
, V
CC
= 3.0V
25
Full
25
Full
2.7
-
-
-
-
-
-
-
3
50
3
50
0.3
0.3
5.5
300
300
300
300
1.0
1.5
V
nA
nA
nA
nA
mA
mA
Supply Current,
Automatic Power-down Disabled
25
Full
LOGIC AND TRANSMITTER INPUTS AND RECEIVER OUTPUTS
Input Logic Threshold Low
Input Logic Threshold High
Input Leakage Current
Output Leakage Current
Transmitter Input Hysteresis
Output Voltage Low
Output Voltage High
I
OUT
= 1.6mA
I
OUT
= -1.0mA
ISL4243E Powers Up (see Figure 7)
ISL4243E Powers Down (see Figure7)
I
OUT
= 1.6mA
I
OUT
= -1.0mA
T
IN
, FORCEON, FORCEOFF, EN, SHDN
T
IN
, FORCEON, FORCEOFF, EN, SHDN, V
CC
= 3.6V
T
IN
, FORCEON, FORCEOFF, EN, SHDN
FORCEOFF = GND (ISL4243E) or EN = V
CC
(ISL4241E)
Full
Full
Full
Full
25
Full
Full
-
2.0
-
-
-
-
-
-
±0.01
±0.05
0.5
-
0.8
-
±1.0
±10
-
0.4
-
V
V
µA
µA
V
V
V
V
CC
- 0.6 V
CC
- 0.1
-2.7
-0.3
-
V
CC
- 0.6
-
-
-
-
-
20
AUTOMATIC POWER-DOWN
(ISL4243E Only, FORCEON = GND, FORCEOFF = V
CC
)
Receiver Input Thresholds to
Enable Transmitters
Receiver Input Thresholds to
Disable Transmitters
INVALID Output Voltage Low
INVALID Output Voltage High
Receiver Threshold to Transmitters
Enabled Delay (t
WU
)
Full
Full
Full
Full
Full
2.7
0.3
0.4
-
100
V
V
V
V
µs
FN8037 Rev 7.00
Jun 10, 2010
Page 5 of 14